There is a known artificial knee joint implant including a tibial component fixed to a proximal portion of a tibia and a femoral component fixed to a distal portion of a femur (see Patent Document 1, for example). The femoral component described in Patent Document 1 includes the medial condyle and the lateral condyle arranged side by side in the left-right direction when the femoral component is fixed to the femur. Each of the medial condyle and the lateral condyle includes a distal condyle facing the tibial component at a posture in which the knee is straightened, a posterior condyle disposed posterior to the distal condyle, and a superior condyle disposed superior to the posterior condyle. The distal condyle, the posterior condyle, and the superior condyle form smooth joint surfaces that extend along the periphery of the femoral component so as to be in contact with the surface of the tibial component. Of these, the joint surface on the superior condyle is curved so as to return toward the anterior side of the femoral component. With such a configuration, the femoral component described in Patent Document 1 can be flexed at least by 160 degrees with respect to the tibial component.